Utilisation of spent tyre pyrolysis char as activated carbon feedstock: The role, transformation and fate of Zn

Utilisation and minimisation of spent tyre stockpiles has been made more viable by pyrolysis activation to produce low-cost activated carbons. The unique chemical composition chars (STPC), particularly the high Zn content, shown affect their subsequent utilisation. Nonetheless, little research examined exactly how these additives and, ultimately, what becomes during process. This paper presents a systematic study effect Zn, ZnO ZnS on physical properties STPC transformation mechanisms CO2 activation. Samples acid-washed with without addition were using fixed-bed reactor in 66.7%v/v for 3 h at 850, 950, 1000 1050 °C. Under conditions, both found act as catalyst activation, increasing surface area, pore volume burn-off. During was reduced C form elemental thermally decomposed release S. Thermogravimetric analysis its compounds above 600 °C, separately mixed char, under confirms that dissociate Zn(v) further reacts or S reform ZnS. However, is progressively removed from carbon temperatures between 950 °C These results have direct implications utilisation SPTC feedstock carbon, production Zn-loaded